This specification relates to dynamic storage resources.
Some data storage systems include integrated buffers. For example, a storage system may include an integrated buffer (e.g., using high-speed semiconductor memory) and provide an interface that uses the buffer in servicing requests for access to underlying storage devices in the storage system. One example of such a buffer arrangement uses a caching approach in which recently read data from the storage devices is kept in buffers so that repeated requests to read the same data can be serviced from the buffers without requiring repeated reads of the underlying storage device. Similarly, data for write requests may use such a buffer. Furthermore, the system may operate according to a semantic model which allows reordering of some requests, such as reordering read requests for a same block of data but not reordering read and write requests for the same block. Devices may use other fixed buffering approaches and associated semantic models. The buffers may be at various scales, for example, being associated with different disk drives, or being associated with substantially larger intelligent storage systems.
Data storage and access interfaces, such as provided by memory or disk controllers, are often configured to operate according to a semantic model that permits the requester to make certain assumptions regarding how requests made through the interface will be handled. In general, the semantic model is fixed for a particular interface or device.
One application of storage devices is for storing and providing access to digital content, such as digital multimedia content. For example, movies can be stored on storage devices for retrieval when the movies are provided to viewers of the movies.